The vision for STEREO/SECCHI was to image solar wind phenomena continuously from their origin in the solar corona to interplanetary space. Analyzing these data is a challenge: the background star field accounts for 99.9% of the total intensity in the field of view of HI-2. However, with sophisticated post-processing techniques it is possible to separate the celestial and zodiacal backgrounds and produce images of excess Thomson scattering in moving structures in the solar wind. The final S/N ratio is high enough to permit quantitative analysis. We have, for example, been able to track the mass of both CMEs coronal disconnection events, as they propagate through the surrounding solar wind. The former can, for the first time, be associated directly with their source flux ropes in the corona; and the latter appear to be the dominant player in balancing the injection of new open flux by CMEs and determining the interplanetary magnetic field strength. These new, quantitative results barely scratch the surface of what can be accomplished with modern heliospheric imaging.